This invention relates to conveyor belts and, more particularly, to modular plastic conveyor belts formed of rows of plastic belt modules pivotally interlinked by transverse pivot rods.
Because they do not corrode, are light weight, and are easy to clean, unlike metal conveyor belts, plastic conveyor belts are used widely, especially in conveying food products. Modular plastic conveyor belts are made up of molded plastic modular links, or belt modules, that can be arranged side by side in rows of selectable width. A series of spaced apart link ends extending from each side of the modules include aligned apertures to accommodate a pivot rod. The link ends along one end of a row of modules are interconnected with the link ends of an adjacent row. A pivot rod journaled in the aligned apertures of the side-by-side and end-to-end connected modules forms a hinge between adjacent rows. Rows of belt modules are connected together to form an endless conveyor belt capable of articulating about a drive sprocket.
In many industrial applications, conveyor belts are used to carry products along paths including curved segments. Belts capable of flexing sidewise to follow curved paths are referred to as side-flexing, turn, or radius belts. As a radius belt negotiates a turn, the belt must be able to fan out because the edge of the belt at the outside of the turn follows a longer path than the edge at the inside of the turn. In order to fan out, a modular plastic radius belt typically has provisions that allow it to collapse at the inside of a turn or to spread out at the outside of the turn.
Apertures slotted in the direction of travel of the belt are commonly provided in the link ends on at least one side of the modules to facilitate the collapsing and spreading of the belt.
It has been known to provide radius belts with side guards to prevent transported articles from falling off of the conveyor belt. The conventional arrangement for attaching the side guards to radius belts has been to hold the side guard between link ends by attachment of one end of the side guard to one of the link ends and by attaching the opposite end of the side guard to the pivot rod adjacent to the link end. This solution has the disadvantage that it may significantly hinder the collapsing of the modules in the curve.
What is needed is a snap-on side guard for a modular radius conveyor belt that does not interfere with the collapsing of the modules and that can be easily assembled and disassembled for cleaning.
The present invention meets the above-described need by providing an endless conveyor belt formed of plastic belt modules and capable of following a curved path. The modules include first and second module surfaces, i.e., a top, product-conveying surface and a bottom, sprocket-driven surface. An intermediate section extends across the width of each module transverse to the direction of belt travel.
A plurality of snap-on side guards are mounted in vertical openings disposed in the belt modules. Each side guard includes a central post having opposed wings extending in a forwardly and a rearwardly direction along the direction of conveyor belt travel. The wings are staggered in the lateral direction so that the forward wing of a first side guard overlaps with the rearward wing of an immediately adjacent second side guard.
Accordingly, the side guards do not interfere with the collapsing of the belt around turns because they are not attached to the pivot rods. Also, because the wings on adjacent modules are offset laterally they are capable of moving relative to one another without interference.